It's back to work for Congress, but not for long -- in four weeks, it will leave town for its month-long August recess.

Here are the most pressing matters on Congress' agenda for July:

Student loans

The interest rate on new federally subsidized student loans doubled from 3.4 percent to 6.8 percent on July 1. Congress needs to roll back this increase before it takes August off, or the cost of a up to 7 million students will face a lot more debt when they return to school in September.

The House passed legislation in May that would peg interest rates for new student loans at 2.5 percentage points above the rate for 10-year Treasury notes, and cap the rate at 8.5 percent. President Barack Obama threatened to veto the bill, saying these interest rates would be too high. The Senate is expected to vote Wednesday on a bill that would extend the current 3.4 percent rate another year, but Republicans are expected to block it.

There'll be lots of finger-pointing rhetoric on this issue, but you can expect this one to get resolved by the end of the month.

Immigration reform

House Republicans will meet Wednesday to talk about their plans for immigration reform, now that the Senate has passed comprehensive legislation. House Speaker John Boehner, R-Ohio, says the House won't simply take up the Senate bill, and there appears to be little appetite among House Republicans for the Senate bill's centerpiece: a pathway to citizenship for immigrants who are in the U.S. illegally.

The question facing the House is whether to bring up other aspects of immigration up for floor votes this month. Candidates could include committee-approved bills that would boost border security, beef up enforcement of immigration laws, overhaul agricultural work visas, and increase visas for high-skilled workers.

Votes on these bills would show the House isn't ignoring immigration reform, but they wouldn't satisfy the broad coalition -- including many business groups -- pushing for comprehensive legislation. Expect lots of press conferences, rallies, advertising campaigns and other lobbying campaigns this month to pressure the House to take up a complete package of immigration reforms.

Health care reform

This week, the House Ways and Means Committee will grill Treasury Department officials on what led to the decision to delay the employer mandate and how this delay will effect the rest of ObamaCare.

"It is time for the administration to explain to the American people why it’s acceptable to grant this delay, while at the same time taking no action whatsoever to provide any relief from the individual mandate,” said Rep. Kevin Brady, R-Texas, who chairs the subcommittee holding the hearing

Congress also will keep an eye on how much progress is being made on setting up new insurance exchanges for individuals and small businesses. These online marketplaces are scheduled to begin enrolling customers Oct. 1.

Federal spending

So sequestration hasn't been so bad, has it? Well, the economy may start feeling more effects from these across-the-board spending cuts this month. Starting today, 650,000 civilian employees of the Department of Defense will get one unpaid day off a week for the next 11 weeks.

These employees work all over the U.S., and this 20 percent pay cut will mean they'll have less money to spend at retailers and other businesses over the next three months.

The federal government's new fiscal year doesn't start until Oct. 1, so Congress likely will put off major budget decisions until after Labor Day. But there will be lots of talk this month about how to replace sequestration with alternative deficit-reduction measures. Plus Republicans are expected to unveil a list of spending cuts they'll insist be enacted in return for an increase in the federal government's debt ceiling. The government is expected to hit its borrowing limit sometime this fall.

Senate confirmations

Republicans have held up confirmation of two of Obama's Cabinet nominees: Thomas Perez as Labor secretary, and Gina McCarthy as Environmental Protection Agency administrator.

Plus, there's no confirmation path in sight for three nominees to the National Labor Relations Board, an agency that could lack a quorum -- and therefore couldn't function -- if at least one of these nominees isn't confirmed by Sept. 1. That might suit business groups just fine, because they contend the NLRB has pursued a pro-union agenda under Obama.

Unions and liberal groups, however, are so frustrated with Republican obstruction of Obama's nominees that they're urging Democrats to change Senate rules so that a simple majority would be sufficient to force a vote on them. Under current rules, nominees in most cases need 60 votes to overcome filibusters.

Such a rule change is called the "nuclear option" because it would make the Senate more like the House -- an institution where the minority party has little power. That may be attractive to Democrats now, but there's a chance Republicans could win control of the Senate in 2014. If that happens, Democrats would miss their right to filibuster.